2. Endurance Exercise Activates Matrix
Metalloproteinases in Human Skeletal Muscle
• Eric Rullman, Jessica Norrbom, Anna Stromberg, Dick Wagsaer,
Helene Rundqvist, Tara Haas, and Thomas Gustafsson
• Journal of Applied Physiology January 2009
3. Endurance Exercise Activates Matrix
Metalloproteinases in Human Skeletal Muscle
• Background / Introduction
• Methods
• Results
• Supplementary data (circulation)
• Summary / Conclusion
4. Background
Skeletal Muscle
• Most changes in function
and structure involves ECM
remodeling
• Physiological / Pathological
• Physical exercise several
factors that could affect
MMP expression
– local ischemia
– increases in muscle stretching
– shear stress, wall tension of
blood vessels
MMP’s
• Remodels / Degrades ECM
proteins
• Physiological / Pathological
• the vast majority of genes
upregulated in response to
exercise training are related
to ECM
8. Method
• 10 - healthy male subjects
• Age 24 (20 –27) yr,
• Height 181 (173–190) cm,
• Weight 75 (63–90) kg,
• VO2max was 51 (43– 64) mlkg-1 min-1.
• Welltrained subjects (VO2max 65 mlkg-1 min-1) were
excluded maximize the subjects’ training responses.
9. Study Design
• Endurance Exercise in the supine position performed
with the dynamic constant-load knee-extension exercise
for 45 min at 60 revolutions/min.
• 45 min of one-legged exercise with a 20% restriction in
blood flow at their highest tolerable workload.
• Then, 45 mins exercise with the opposite leg without
blood flow restriction at same workload as first leg
– 4x / week for 5 weeks
10. Study Design
• Muscle biopsies were obtained
• Biopsy from vastus lateralis of both legs:
– pre and 2 h after the first exercise bout
– after 10 days of training
– after 5 wk of training
11. Testing
• Immunohistochemistry
• RNA Extraction and Reverse Transcription
– mRNA expression
– MMP2, MMP9, MMP14, & TIMP1
• Laser Capture Microdissection
– mRNA express and activity within multiple cell types
– 3 subjects only
– mRNA for MMP2 only
– Pre and 10 days only
• Protein Extraction and Zymography
– Enzyme activity
– Pro-MMP9, active MMP9, & MMP2 only
– All time points
20. Summary
MMP2
• No change after single
bout of exercise (R or
UR)
• Maintained elevated
expression and activity
from Day 10 to Wk 5
• Enzymatic activity
scattered (in ECM and
ICM of muscle, but more
intense adjacent to
capillaries)
MMP9
• Significant change in (Pro
and Activated MMP9)
expression and activity after
single bout of exercise (R &
UR)
• Maintained elevated
transcription after Day 10,
however not significant
because of high variance
• Enzymatic activity only
found in ECM around
muscle and capillaries, not
within
21. Summary
MMP14
• Expression and activity
followed the same trend
as MMP2
TIMP1
• Transcription increased at
every data collection
point, however, not
significant until after Day
10
22. MMP-9 and Circulation
• Circulating MMP-9 during exercise in humans
– E. Rullman, K. Olsson, D. Wagsater, T. Gustafsson
23. Study Design
Subjects
• Ten healthy male subjects
• Age: 25 (18–37) years
• Height: 180 (170–190)
cm
• Weight: 77 (58–82) kg
• (VO2max) 3.7 (3.1–4.3) L
min-1.
Exercise and Method
• Exercise perrformed on
an electrodynamically
loaded cycle ergometer
• 60 min of cycle exercise
• Graded increases in
intensity
• Femoral blood draws at
27mins, 57mins, and
120mins after end of Ex.
24. Results
MMP9
• No significant difference in
Femoral Artery and
ipsilateral Femoral Vein
before exercise
• Significant increase in both
Femoral Artery and Femoral
Vein 27mins after exercise
• no evidence of neutrophil
degranulation to coorelate
with MMP9 turnover
associated with Collagen IV
degradation
Type IV Collagen
• No significant difference
in Femoral Artery and
ipsilateral Femoral Vein
before exercise
• Significant increase in
both Femoral Artery and
Femoral Vein 27mins and
57mins after exercise
25. Questions
• Eric Rullman, Jessica
Norrbom, Anna Stromberg,
Dick Wagsater, Helene
Rundqvist, Tara Haas, and
Thomas Gustafsson
• Endurance exercise
activates matrix
metalloproteinases in human
skeletal muscle. J Appl
Physiol 106: 804–812, 2009.
• E. Rullman, K. Olsson, D.
Wagsater, T. Gustafsson
• Circulating MMP-9 during
exercise in humans. Eur J
Appl Physiol (2013) 113:1249–
1255
